09.05.12 4:25 AM ET

Oh, sure, she did the job subtly—and leavened with many heart-tugging stories about both her own family and the other remarkable American families she gets to meet as first lady. Courting a broad audience, she also skipped the more inflammatory lines from her stump speeches: no direct jabs at the other guy.

In fact, she didn’t even mention the name of the other guy at all.

She did, however, spend a fat chunk of tonight’s address painting a picture of her husband that stood in clear contrast with that of a certain unnamed Republican nominee.

Unsurprisingly, the Democratic delegates on the floor of the arena ate it up.

First came the heart-warming stories about President Obama’s up-from-nothing roots. Most of us are by now familiar with the basics: “Barack was raised by a single mother who struggled to pay the bills and by grandparents who stepped in when she needed help ...”

The unspoken but unavoidable corollary: guess which candidate never faced any of these character-building challenges?

After establishing her and Barack’s regular-folk cred, Michelle went through some of the lessons learned from their life experience. For instance: “We learned about dignity and decency—that how hard you work matters more than how much you make.” (Take that, Mr. Owns-His-Own-Car-Elevator.)

And: “We learned about honesty and integrity ... that the truth matters ... that you don’t take shortcuts or play by your own set of rules ... and success doesn’t count unless you earn it fair and square.” (Hmmmm. Wonder whom she had in mind as playing fast and loose with, say, tax laws?) It was at this point the delegate sitting next to me began whooping and clapping and yelped, “That was a good shot!”

Not one to duck a fight, Michelle even doubled down on that whole you-didn’t-build-that-by-yourself notion that has given the president so many headaches of late, noting how she and Barack “learned about gratitude and humility” from all those people who “had a hand in our success, from the teachers who inspired us to the janitors who kept our school clean.”

Those are our values, she told the crowd. “That’s who we are.”

Why does that matter so much?

Glad you asked. Because, Michelle asserted, presidents can have the wisest advisers in the world. “But at the end of the day when it comes time to make that decision, as president, all you have to guide you are your values, your vision, and the life experiences that make you who you are.” (The ladies sitting behind me were crazy for that line.)

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And just in case anyone missed her point: “So when it comes to rebuilding our economy, Barack is thinking about folks like my dad and like his grandmother.” (While the upper-crusty Mitt Romney is thinking about ...)

Again and again, Michelle labored to link President Obama’s values and policies to his own experiences. (Why does he fight so hard for affordable student loans? Because when he and Michelle were first married “our combined monthly student loan bill was actually higher than our mortgage.”)

And on and on she went, building toward the message: “So in the end, for Barack these issues aren’t political, they’re personal. Because Barack knows what it means when a family struggles ... Barack knows the American Dream because he’s lived it, and he wants everyone in this country to have that same opportunity, no matter who we are, or where we’re from, or what we look like, or who we love.”

Yep. She even managed to slip in that pitch for marriage equality.

Just as key, Michelle told us, the president believes that once you’ve made it through that door of opportunity, “you do not slam it shut behind you. No. You reach back.” (Cue the fist pumping from my seatmate.) “For Barack, success isn’t about how much money you make. It’s about the difference you make in people’s lives.” (Zing.)

It was by no means a harsh or partisan or angry speech. But it was fiery, and it had a very clear aim.

Four years in, the first lady has clearly learned how to play this game.